"Complaint and Affidavit known by me, or told to me by other reliable persons form the basis for my belief"
It is my belief that this affidavit is based solely on the events as described by CBR, whom they had reasonable belief, based on their investigation to date had murdered MT.
LE may have other theories, but this was the first time they had interviewed CBR, they had not executed a search warrant on either his place of residence, the vehicle, or any other areas of investigation that were of interest to LE. CBR still had possession of his cell phone, so they had not even had the time to examine the contents or once again execute a search warrant on it or any other devices.
This affidavit is solely CBR's version of events.
MOO
ETA Save for some brief observations of LE, such as the clothing found.